Why don't I have an AIR FILTER?

I have an air silencer but according to my dealer my 2004 sportster LE DI does not have an AIR FILTER. Other than Sea Doo trying to suck out every last drop of HP out of that engine does anyone know why Sea Doo would rather have my boat ingest dirty air?

Your boat, like mine and most others, has a flame arrestor inside that airbox. The flame arrestor is a series of metal mesh panels that are meant to not necessarily prevent backfiring, but prevent flames from coming back into the silencer and engine compartment. It also functions as somewhat of an air filter, though it may not be the same kind of filter used on other engines. The flame arrestor reminds me of a grease filter in a range hood (if you know what that looks like). It allows exhaust air out thru the vent, but keeps the grease out of that vent. Simple analogy, but simple works. The flame arrestor is a USCG requirement, an air filter is not. Besides, I don't think dirty air is as much an issue in a marine environment as it might be with an ATV in an off-road environment. Just my 2 cents...